1. Technical Field
The present invention relates to an apparatus and method for detecting arc, more specifically to an apparatus and method for detecting arc in which by sensing arc occurred in process chamber for plasma treatment with RGB color sensor portion, color data of the arc can be obtained at high speed.
2. Description of the Related Art
Generally, apparatus for plasma treatment is widely used in semiconductor manufacturing process, liquid crystal display panel manufacturing process, solar cell manufacturing process, surface treatment process of material, treatment for atmospheric pollution, nuclear fusion and the like.
Particularly, plasma treatment apparatus used for manufacturing semiconductor generally uses RF electric source for producing plasma, and in plasma treatment process, if there are structural defect or small particles in process chamber, arc deteriorating stability of plasma treatment process may occur.
Particularly, in a plasma treatment apparatus used for manufacturing semiconductor, it is difficult to find out in which element of a wafer defect is occurred by the arc, and the arc may produce other small particles causing defects of element in next process.
By this, for monitoring stability of the plasma treatment process, technique for monitoring occurrence of arc in process chamber is demanded.
Detecting of the arc was performed by apparatus for detecting arc by monitoring RF signals in process chamber.
However, method for detecting arc using the RF signal has the problem that by the method it is difficult to catch prelude phenomenon in which signal of specific intensity is detected before occurrence of arc, because the method is a type merely counting variation value of RF signal frequency.
That is, the method of detecting arc using RF signal can detect only occurrence of arc, so there is a limit to figure out the characteristic of the arc and analysis of the arc.
Accordingly, to solve said problem and at the same time to figure out prelude phenomenon and characteristic of arc occurrence, method of monitoring arc through optical analysis of inside of the process chamber was developed.
The method is performed by installing CCD camera in the process chamber, and by analysis images photographed by the camera to detect arc.
However, the method for detecting arc with the CCD camera stores to analyze images of inside of the process chamber photographed by the camera, size of data to be stored is very large (10 Gbyte per hour), and number of images to be analyzed is very large, so it makes it difficult to detect arc effectively and easily.
Accordingly, it is demanded to develop a technique for solving said problem, and enabling easy monitoring for arc, to figure out prelude phenomenon and characteristic of arc occurred in process chamber based on data processing at high speed.